Fuse for antitank mines



March 2, 1948. J. B. TRAYLOR FUSE FOR ANTITANK AMINES 2 Sheets-Sheet 2 Filed OC.. 14, 1943 Patented Mar. 2, 1948 UNITED STATES PATENT OFFICE FUSE Fon ANTITANK MINES John B.'Traylor, Denver', Colo.

Application October 14, 1943, Serial No. 506,190

11 Claims. (CL 102-70) (Granted under the act of March 3, 1883, as

The invention described herein may be manuiactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to an improved fuse for an explosive, particularly an antitank mine. Whereas the usual fuse mechanism in a mine is so designed that a single contact activates the mine; it is the purpose of this invention to provide a skip fuse whereby a mine may be activated either by the rst or by such subsequent contact as may be desired.

vSkip fuses constructed in accordance with this invention and used to activate antitank mines would permit an innite variety of patterns for the layout of mine fields to be used to impede, harass, or confuse the enemy in accordance with the V'tactical requirements.

For example, in a rapid enemy advance over a suspected mine eld, the enemy scout tanks sent ahead to locate mines and clear a path would pass undamaged 'over the mines equipped with skip fuses set for activation on the second contact, but enemy forces following them would activate the mines on contact.

In an enemy advance -of tanks followed by infantry, the tanks would pass over such a mine field into trapped positions unable to retreat without activating the mines and the foot troops following them would, upon contact, activate the mines.

In an enemy advance against retreating friendly tanks, the latter would pass `over such a eld on a prescribed course so as to contact the mines only once, then pursuing enemy tanks would, upon contact, activate the mines,

In case of a feint by friendly forces, mines set for activation `on the third contact would be planted in positions such that the friendly tanks would proceed over them making first contact on` their way to attack the enemy, later withdrawing over the'mines to make the second contact, whereup the mines are left in such condition that contact by the pursuing enemy forces would activate them.

The foregoing illustrations show clearly the desirability of a skip` fuse for mines in accordance with this invention.

Accordingly, it is an object .of this invention to provide an improved fuse or detonatlng mechanism for explosives, particularly antitank mines.

The particular object of this invention is to provide for an antitank mine which may be activated only by the rst or -bysuch subsequent contact asmay be desired. g

amended April 30, 1928; 370 0. G. 757) a fuse requiring an initial contact by a body of large mass, such as a tank and thereafter be in condition for actuation by light weight contact such as by personnel.

The specic nature of the invention as well as otherl objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawings in which:

Fig. 1 is a top elevational View of the fuse.

Fig. 2 is a longitudinal sectional view taken` along the plane 2-2 of Fig. 1 showing the fuse in assembled relation to the body of the mine,

Fig. 3 is a .longitudinal sectional view taken along the plane 3-3 of Fig. 1. g Fig. 4 is a View similar to Fig. 2 showing the fuse in the fired position. g

Fig. 5 is a view showing the development ofthe fuse sleeve and the fuse cam. Y A

Fig. 6 is a side elevational view of the fuse housing. Y Fig. 7 is a crossV sectional View of the fuse taken along the plane 'I-'l of Fig. 2.

Fig. 8 is a side elevational view of the firing pin.

Fig. 9 is a bottom view of Fig. 8'.

' In Fig. 2 is shown in assembled relation a skip fuse mechanism in position in `a mine. The mine casing I is shown cut away to reveal the recess 2 in which is located the fuse assembly. In the center of the bottom of the recess 2 is located the percussion cap 3 which activates the detonating charge (not shown) of the mine.

. A hollow sleeve 8 is secured to' casing I,con centrically positioned with respect to Vcap3. A firing pin 4 is mounted within the sleeve 8. Fir-` ing pin 4 is in the form of a hollow cylinder open at the upper end. The lower end is formed to a small tip 5' of suitable proportions for activating the percussion cap 3. Back of the tip 5 the firing pin is provided with a cone shaped surface 6, the cone shaped surface 6 resting on two balls l which are held in place by holes 9 in' sleeve 8, A hollow cylindrical housing I3 is mounted around sleeve 8 and retains the balls 1 within sleeve 8 against the camming action of cone shaped 'surface 6.'

Extending out from the side wall of the firing pin 4 is a pin I 0 whichfits into a longitudinal groove Il in the inside of the sleeve 8 and hence keeps the firing pin 4 and the sleeve 8 in longitudinal alignment. Within the hollow cylinder of the ring pin 4 is Vlocated a helical spring I2 extending from the inside bottom of the firing A further object of this invention is* to provideA vactivation of the 'fuse while handling.

3 pin 4 to the inside top of the plunger housing I3. The ends of the spring I2 are formed into nubs I4 which it into holes I5 and IB respectively in the ring pin Il and the housing I3. Spring I2 is assembled to produce a torsional bias between ring pin 4 and plunger housing I3.

The housing I3 ts loosely into the recess 2 in the mine vcasing I and serves as a housing for the fuse mechanism and also as the depressor for activating the fuse. f

At the time of assembly, the sleeve .-8 and the housing I3 are fixed in relationship by the shear pins I'I which fit into holes I8 and I9 in the housing and sleeve respectively, hence preventing downward movement of plunger housing I3 until subjected to a force greater than the shear re' sistance of pins I 'I. Y .Y

In the inner wall of the housing i3 is 'located a pin 20 which, in assembly, fits into groove 2I in the. outer wall of sleeve 8. The` layout of the sleeve 8 is shown in Fig. '5. The layout shows three vertical sections of the groove, but there may beany number corresponding Vto the number of contacts desired to cause activation.

On the outside of the sleeve B and in a position 911 from the groove II is located the iirst section of a cam 'guide groove v2I which is shaped as shown lin "the'developed view of Fig. 5. The construction shown here requires three successive contacts to actuate the mine but it will be understood 'that the guide groove l2I may be convenientlymodied "to actuate the mine `after any desired number .of vsuccessive contacts. "The second and 'third vertical .sections of the groove are 45 and 96 respectively to the right `of the vfirst section. Two holes 9 in ,sleeve 8 are in diametrical alignment with the rst Isection of the groove 2l.

In the Ahousing I3 there areprovided two holes 22 ylocated in diametrical alignment with the third section of the groove 2| and at such a height that when pin 2D is in the third section of groove 2| and the housing I3 is depressed to the bottom of the recess .2, the holes 2.2 are in :alignment with holes 9 in the sleeve 8. Holes 9 and 22 are of the same size and the thickness of the wall of the housing AI3 pi-us that of the sleeve 8 is greater than the diameter of ball 1 so that when alignment isobtamed, the :balls 'i are 'forced into the space provided by the two pair of holes 9 and y22, allowing the iiriing pin f4 unimpeded movement to contact with'the .percussion cap '3 under the bias of spring i2.

A lock not l(not shown.) or any'other suitable device may be 'used to retain the fuse assembly in the mine casing, and also prevent the housing I3 fromrising beyond the position shown in Fig. 1 after the pins H have been sheared.

Anaccordion formed collar 23 of metal foil fits around the joint between the mine case I and the housing :I3 sealing :the junction Vagainst water or dirt..

When assembledthe sleeve 8 is located Vinixed relationship to the housing I3 by the two shear pins ltil. This'prevents misassembly or accidental It also prevents accidental activation by personnel after them-line has been planted. The shear strength of thepins is preferably such that the pins will be'sheairezdtand the Vmine thereby rendered lsensitive foy small tanks or vehicles after lwhich even foot :pressure will be :sufcient to activate it. A total ishear strength for the two pins I I of .about 50B .pounds and.aroompressionstrength in spring I2 of about 100 pounds would meet these conditions.

When assembled the guide pin can be located in the first, second or third section of groove 2| as may be desired in order to bring about activation on the third, second or rst contact respectively.

If activation on the third contact is desired, the fuse mechanism is assembled with the pin 20 iin position in the third section in the guide groove 2l. When contact is made by a tank or vehicle, the weight on top of the mine depresses the housing lathereby shearing the pins I'I and forcing vthe housing down till it rests on the bottom of the recess 2 in the mine casing I (Fig. 3). In thisposition the guide pin 20 is in the bottom of the first section of the groove 2| whereupon Y the spring I2 which exerts a torsional bias causes rotation of housing I3 with respect to ring pin il and sleeve 8 causes rotation of the firing pin and sleeve to the lpoint where pin2 enters the second section of groove 2I. When the load is removed from the housing I3, the compressive forceV of spring i2 causes the housing to rise and the firing pin t and sleeve 8 turntill they come to rest with the ,guide pin 2Q in position 20a.

The fuse mechanism is'now ready for the second contact which would .again force lthe housing I3 down into contact with the bottom of the recess 2. Much less force is required for this contact since the shear pin i-'I has been 4broken previously. The torque in spring I2 would then cause rotation of housing I 3 till the pin 2l! entered the third section of the groove 2l.. .In this position the fuse mechani-sm is ready for the third, and in this example the rfinal contact. The plunger housing vI3 has now been rotated with respect to sleeve 8 so that the holes 9 in the sleeve 8 are in vertical alignment with the holes 22 in the housing I3. When the plunger housing is next depressed, holes 22 come into full alignment with holes 9 in the sleeve 8 and the balls I .are forced into the holes 22 in the housing I3, allowing the ring pin 4, now under the press-ure of the fully :compressed spring I2, to move downward `and strike the percussion cap 3 (Fig. 4).

It will be readily seen that with even three possi-ble settings `of the skip fuse offer there is an almost endless variation in the tactical use of antitank mines equipped therewith. Furthermore, the shear pin feature makes possible the placing .of such mines for ultimate use as either antitank .or antipersonnel mines, without danger to personnel handling and placing them,

l claim:

1. A fuse comprising a firing member, a locking member yand va plunger member mounted in telescoping relation, said iiring member and said plunger member being movably Amounted with respect to said locking member, a. primer arranged :in the path of said liring member, a resilient means operative between said firing member and said plungermember, `said locking member having a hole thru a wall thereof, a locking ball mounted in said hole in said locking member, said locking ball projecting in the path of said nring member to hold said ring member out of engagement with said primer, said plunger member having a recess arranged to align horizontally vwith said hole in said locking member upon movement of said plunger member toward said primer, means for aligning said recess and said hole .radially upon movement of rsaid plunger member away from vsaid primer, whereby said recess and said hole may :healigned horizontazliy and 'radially upon reclproca'tionl of the Aplunger member and a'cam surface on said firing member contacting said'locking ball and operative to cam said ball into said recessof said plunger member, whereby said firing member is freed to strike said primer under force'of said resilient means.

2. A fuse comprising a ring member, a locking member and a plunger member mounted'in telescoping relation, Vsaid ring member and said -plunger member being mounted on said locking member for axial movement with respectv thereto, a primer arranged in the path of said ring member, means preventing rotational movement of said firing member with respect to said locking member, resilient means operative between said plunger member and sai-d firing member, said resilient means arranged to fbias said plunger member rotationally with respect to said firing member and to oppose relative axial movement of said plunger member with respect to said firing member, means permitting limited unidirectional rotational movement of said plunger -member with respectv to said locking member under the bias of said resilient means when said plunger member is reciprocated axially, said locking member having a hole thru a wall thereof, a locking lball mounted in said hole in said locking member, said locking ball projecting into the path of said firing member to hold said ring member out of engagement with said primer, said plunger member having a recess located with respect to said locking member so as to align with the said hole in said locking member when said plunger member hasbeen rotationally advanced with respect to said locking member by a predetermined number of axial reciprocations of said plunger member, and a cam surface onsaid firing member contacting said `locking ball and operative to cam said ball into said recess of said plunger member when said recess is aligned therewith, whereby said Vfiring member is freed to strike said primer under force of said resilient means.

3. A fuse comprising a firing member, a locking member, and a plunger member mounted in'telescoping relation, said firing member andv said plunger member being mounted on said locking member for axial movement with respect thereto, a primer arranged in the path of said iiring member, means preventing rotational movement of said ring member with r-espect to said locking'member, resilient means operative between said plunger vmember and said firing member, said resilient means arranged to bias said plunger member rotationally with respect to said iiring member and to oppose relative axial movement of said plunger member with respect to said ring member, a pin on said plunger member cooperating with a cam slot on said locking member to permit limited rotational movement of said plunger member with respect to said locking member under the bias of said resilient means when said plunger member is reciprocated axially, said locking member having a hole thru a wall thereof, a locking ball mounted in said hole in said locking member, said locking ball projecting into the path of said 'iiring member to hold said nring member out of engagement with said primer, said plunger member having a recess located with respect to said locking member so as to align with the said hole in said locking member when said plunger member has been rotationally advanced with respect to said locking member. bya predetermined number of axial reciprocatlons of saidplunger member, and a cam surface on said firing member contacting said locking ball and operative to cam said ball into said recess of said plunger member when said recess is aligned therewitnwhereby saidil'ring member is freed to strike said primer under force of said resilient means.

4. A fuse comprising a firing member, a locking member, and aV plunger member mounted in telescoping relation, said iiring member and said plunger member being mounted on said locking member for axial movement with respect thereto, a primer arranged in the path of said firing member, means preventing rotational movement of said firing member with respect to said locking member, resilient means operative between said plunger member and said firing member, said resilient means arranged tobias said plunger member rotationally with respect to said ring member and to oppose relative axial lmovement of saidplunger member with respect to said firing member, means permitting limited unidirectional rotational movement of said plunger member with respect to said locking member under the bias'of said resilient means when said plunger member is reciprocated axially, said locking member having a hole thru a wall thereof, a locking ball mounted in said hole in said locking member, said locking ball propecting into the path of said firing member to holdsaidrring member out of engagement with said primer, said plunger member having a recess located with respect to said locking member so as to align with the said hole in said locking member when said plunger member has been rotationally advanced with respect to said locking member by a predetermined number of axial reciprocations of said plunger, a cam surface on said ring member contacting said locking ball an-d operative to cam said ball into saidrecess of said plunger member when said recess is aligned therewith, whereby said firing member is freed to strike said Yprimer under force of said resilient means, and a shear pin preventing movement of said plunger member under applied forces less than the shear strength of said pin.

5. A fuse comprising a casing defining a cylindrical recess, a percussion primer mounted in the base of said recess, a hollow locking cylinder concentrically secured in said recess, a plunger mounted laround said locking cylinder and arranged to slide thereon, a firing pin slidably mounted within said locking cylinder and arranged to move into contact with said primer, resilient means operative between said plunger and said ring pin, said locking cylinder having a hole thru a wall thereof, a locking ball mounted in said hole in said locking cylinder, said locking ball projecting in the path of said ring pin to Vholdvsaid ring pin out 'of engagement with said primer, said plunger having a recess arranged to align horizontally with said hole in said Vlocking cylinder upon movement of said plunger toward said primer, means for aligning said recess and said hole radially upon movement of said plunger member away from said primer, whereby said recess and said hole may be aligned horizontally and radially upon reciprocation of the punger member, and a cam surface on said ring pin contacting said locking ball anld operative to cam said ball into said recess of said plungenwhen said recess is aligned therewith,` whereby said ring pin is freed to 7 Vstrike said prmerlunder force of said resilient means.

fi. A :fuse comprising a casing defining a cylindrical recess, -a percussion primer mounted in the base of said recess, a. hollow locking cylinder concentrically ysecured in said recess, a plunger vmounted around said locking cylinder and arranged to slide thereon, a iiring pin slidably mounted within said locking cylinder and arranged to move into contact with said primer, means preventing rotational movement of said firing pin with respect to said locking cylinder, resilient means operative between said plunger and said ring pim-said resilient means arranged to bias said plunger rotationally with respect to said firing pin and to oppose relative axial movement of said plunger with respect to said firing pin, means permitting limited unidirectional rotational movement of said plunger with respect to said locking cylinder under the bias of said resilient means when said plunger is reciprocated axially, .said locking cylinder having a hole thru wall thereof, a locking ball mounted in said hole in said locking cylinder, said locking ball projecting into the path of said firing pin to hold said yhrlng pin out of engagement with said primer, said plunger having a recess located with respect to said locking cylinder so as to align with .the .said hole in said locking cylinder when said plunger has been rotationally :advanced with respect to said ,locking cylinder a predetermined number of axial reciprocations `of said plunger, and a cam surface on said ring pin contacting said locking ball and operative to cam said ball into said recess of said punger when nsaid recess is aligned therewith, whereby said firing pin is freed to strike said primer under force of said resilient means.

"1.. A fuse comprising a casing dening a cylindrical recess, a percussion primer mounted in the base of Ysaid recess, a hollow locking cylinder concentrically secured in said recess, a

plunger mounted around 'said locking cylinderA and arranged to :slide thereon, a iiring pin slidably mounted within .said locking cylinder and arranged to move into contact with .said primer, means preventing rotational movement of said firing pin with respect to said locking cylinder, resilient means operative between said plunger and said firing pin, said resilient means arranged to bias said plunger rotationally with respect to said iirng pin and to oppose relative axial movement of said plunger with respect to said ring pin, a. .pin on plunger cooperating with a cam slot on said 'locking cylinder to permit limited rotational movement of said plunger with respect to said locking cylinder under the bias of said resilient means when said plunger is reciprocated axially, said locking cylinder having a hole thru a wall thereof, a locking ball mounted in said hole in said locking cylinder, said locking ball projectinginto .the path `i said firing pin to hold said ring pin out of engagement with said primer', said plunger having a recess located with respect to said locking cylinder so as to align `with the said hole in said locking cylinder when said plunger has been rotationally advanced with respect to said locking .cylinder by :a predetermined number of axial reciprocations of said plunger, and a .camsurface on said firing pin vcontacting said locking ball and operative to ycam said lball .into said recess of said plunger when said recess is aligned therewith, whereby said ring pin is -freed to strike said primer :under force of said resilient means.

8. A fuse comprising a casing defining a cylindrical recess, a percussion primer mounted in the base of said recess, a hollow locking cylinder concentrically secured in said recess, a plunger mounted around said locking cylinder and arranged to slide thereon, a iring pin slidably mounted within said locking cylinder and arranged to move into contact with said primer, means preventing rotational movement of said iirng pinwith respect to said locking cylinder, resilient means operative between said plunger and said firing pin, said resilient means arranged to bias said plunger rotationally with respect to said firing pin and to oppose relative axial movement of said plunger with respect to said ring pin, means permitting limited unidirectional rotational movement of said plunger with respect to said locking cylinder under the bias of said resilient means when said plunger is reciprocated axially, said locking cylinder having a hole thru a wall thereof, a locking ball mounted in said hole in said locking cylinder, said locking ball projecting into the path of said firing pin to hold said firing pin out of engagement with said primer, said plunger having a recess located with respect to said locking cylinder so as to align with the said hole in said locking cylinder when said plunger has been rotationally advanced with respect to said locking cylinder by a predetermined number of axial reciprocations of said plunger, a cam surface on said firing pin contacting said locking ball and operative to cam said ball into said recess of said plunger when said recess is aligned therewith, whereby said firing pin is freed to strike said primer under force of said resilient means, and a shear pin securing said plunger to said casing to prevent movement of said plunger member under applied forces less than the shear strength of said pin.

9. A fuse comprising a iiring member, a locking member, and a plunger member mounted in telescoping relation, said firing member and said plunger being movably mounted with'respect to said locking member, a primer arranged in the path of said firing member, resilient means located between said firing member and said plunger member for separating said two members and constructed and arranged for rotating said locking member andplunger member relative to each other, locking means operative between said ring member and said locking member for holding said firing member out of engagement with said primer, andv guide means rotatably connecting said plunger and said locking member, operative by longitudinal movement of said plunger, for releasing said locking means from engagement with said firing member whereby said iiring member is freed to strike said primer under force of said resilient means.

10. A fuse comprising a ring member, a locking member, and a plunger member mounted in mittlng a controlled relative rotation of said locking member and said plunger, operative by longitudinal movement of said plunger, means operative upon a predetermined rotation and longitudinal movement of said plunger relative to said locking member for releasing said locking means from engagement with said firing member whereby said rlng member is freed to strike said primer-under force of said resilient means, and a shear pin preventing movement of said plunger member under applied forces less than the shear strength of said pin.

11. A fuse comprising a casing having a cylindrical recess, a percussion primer mounted in the bottom of said recess, a sleeve concentrically disposed in said recess, a plunger surrounding said sleeve and arranged to slide thereon, 'a striker member slidably mounted within said sleeve and having a firing pin for contacting said primer, spring means between the plunger and 20 striker biasing them longitudinally and angularly, detent means carried by the sleeve and JOHN B. TRAYLOR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name I Date 1,366,623 Woodberry Jan. 25, 1921 1,514,743 Taylor Nov. 11, 1924 1,549,763 Greenwell Apr. 18, 1925 2,376,332 Adelman ---1 May 22, 1945 FOREIGN PATENTS Number Country Date Great Britain Dec. 4, 1941 

